This product, designed in collaboration with teachers, covers a number of topics rich in automation, particularly in the areas of electrical engineering education and the maintenance of automated systems. The SPH400 dedicated pumping station is a scale replica of a small distribution network in the city and surrounding countryside that is powered by a water storage tank. This system was chosen because: the variable number of users, the very large fluctuations in water reserves have collected, especially in summer, a large water supply because the installed capacity of the system can not meet this strong demand for water. flow during these periods. We want to model the rural pumping station including: a well in relation to the water table; a buffer tank; A water tower The water pump in the water table and filled with a buffer. Three pumps take this water and fill a water tower. Three solenoid valves placed on the water tower simulating household consumption with a return of water to the tarpaulin.
Description of constituents :
The "well" consists of a bin with a manual drain valve located at the lowest point of the system.
The dewatering pump consists of a centrifugal pump driven by a three-phase cage asynchronous motor, which itself is driven by a U / f speed controller.
The transparent 60-liter buffer tank is equipped with an analog level sensor which, in conjunction with the industrial programmable logic controller and the U / f drive, provides a PID control of the water level in the buffer tank. In addition, two on-off sensors control the min levels. and max. of this buffer tank. A pipe with a manual ball valve connects the buffer tank to the "well". This pipe allows a discharge rate greater than the flow of the dewatering pump.
From this buffer tank, three centrifugal pumps driven by three three-phase asynchronous cage motors fill the transparent water tower.
Household consumption is modeled by three solenoid valves allowing manually by pressing three push buttons or automatically by the programmable logic controller, to simulate the different consumption regimes by return of the water of the "water tower" at the "well".
These three solenoid valves are placed on 3 pipes of different sections to find 7 different flow rates by combinations of the three solenoid valve controls.
The water tower is equipped with three all-or-nothing sensors. Two to capture the min levels. and max., the third for the average nominal level. The latter makes it possible to maintain a level ensuring sufficient hydrostatic pressure in the distribution network. Depending on the household consumption (1, 2 or 3 solenoid valves supplied) 1, 2 or 3 repeating pumps will be started. The automation is controlled by a compact industrial PLC. A communication module is installed and allows the dialogue with a PC over serial link. The diagnostics, setpoints and maintenance messages are sent on a "liquid crystal" type display with 2 message lines.
The compact industrial programmable logic controller is equipped with a PID control unit. The system is equipped with all the safeties to ensure safe operation and maintenance. This bench complies with standard C.E. The control components of the system (PLC, pre-actuators, etc ...) are placed in a metal cabinet located so as to
allow easy interventions safely. The system is equipped with wheels (with lock) allowing its movement.
a) Operative part :
Mobile chassis incorporating :
-1 well of water catchment
-1 pool of recovery
-1 water tower
-1 dewatering group (stainless steel centrifugal pump
-3 recovery groups (stainless steel centrifugal pumps
-1 analog flow sensor and a pressure gauge on the dewatering system circuit
-5 digital level sensors
-1 analog level sensor
-3 solenoid valves
b) Control part :
-An electrical cabinet integrating:
-A PLC with analog and digital outputs and inputs, a PID control block, 2 communication interfaces
-A terminal console for operating dialogue
-A digital frequency converter
-Devices for supply and protection of the installation